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171.
We have started the construction of a nationwide forensic soil sediment database for Japan based on the heavy mineral and trace heavy element compositions of stream sediments collected at 3024 points all over Japan obtained by high-resolution synchrotron X-ray powder diffraction (SR-XRD) and high-energy synchrotron X-ray fluorescence analysis (HE-SR-XRF). In this study, the performance of both techniques was demonstrated by analyzing soil sediments from two different geological regions, the Kofu and Chiba regions in Kanto province, to construct database that can be applied in the future to provenance analysis of soil evidence from a crime scene. The sediments from the quaternary volcanic lithology of the Chiba region were found to be dominated by heavy minerals of volcanic origin - orthopyroxene, clinopyroxene, and amphibole, and the REEs (rare earth elements) within the region showed similar geochemical behavior. On the other hand, four distinct heavy mineral groups were identified in the sediments of the Kofu region, where there is a great variety of underlying bedrock, and the geochemical behavior of the REEs in the sediments also varied accordingly to their geological origins. As such, our study shows that high-resolution SR-XRD data can provide information on the spatial distribution patterns of heavy minerals in stream sediments, playing an important role in determining their likely geographical origin. Meanwhile, the highly sensitive HE-SR-XRF data allow us to study the geochemical behavior of trace heavy elements, especially the REEs in the sediments, providing additional support to further constrain the likely geographical origin of the sediments determined by heavy minerals.  相似文献   
172.
Crime prevention strategies are implemented to reduce the damage caused by crimes with CCTV (Closed-Circuit Television) being broadly accepted as one of the main strategies. However, along with CCTV's perceived high expectations as crime deterrent, there is also a growing controversy over CCTV's potentially unexpected limitations. For example, the crime displacement (the presence of CCTV will change the locations of crime and its total number will not change) and the diffusion effects of crime control benefits (the crime prevention effect of CCTV may filter through to neighboring areas) are the representative controversial issues. In this study, we aimed to verify the crime displacement and the diffusion of benefit of open-street CCTV by analyzing the crime tendencies empirically.Gwang Myeong City in Gyeonggi Province, South Korea was chosen to analyze the crime displacement using the WDQ (Weighted Displacement Quotient) which compares the crime tendency of a location with that of its neighboring areas. The results showed that the crime prevention effect of the CCTV was significant. The number of robberies and thefts in the areas with CCTV installed reduced by 47.4%, while the areas without CCTV showed practically no change in the number of crimes. The crime displacement caused by the CCTV was not either found or inconsequential, and the crime rates in the neighboring areas also decreased slightly. Of major cause for concern was the fact that CCTV was marginally effective in deterring violence and as such, there should be a more detailed scientific analysis of the pattern and type of crimes committed in an area where CCTV's are being installed.  相似文献   
173.
Book reviews     
He Bochuan, China on the Edge: The Crisis of Ecology and Development, Berkeley: Pacific View Press, 1991.

Hu Ping, Zai lixiangyu xianshi zhijian (Between Ideal and Reality). Hong Kong: Tianyuan shuwu, 1990.

Hu Ping, Gei wo yige zhidian (Give me a Fulcrum). Taiwan: Lianjing chuban Gongshi, 1988.

Shi Bo, Waimenggu duli neimu (The inside story of Outer Mongolia's independence) (Beijing: Renmin Zhonguo chubanshe, 1993), 479pp, illustrations, maps.

Michael David Kwan, Broken portraits: Personal encounters with Chinese Students, San Francisco: China Books & Periodicals, 1990.

Liang An Guanxi yu Zhongguo Qiantu: Xueshu Yantaohui Lunwenchi (The Taiwan‐Mainland Relationship and the Future of China: Proceedings of a Scholarly Conference), Taipei, Taiwan: Minchu Jijinhui (Democracy foundation), 1992. 390 pages.  相似文献   

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A gas chromatography–mass spectrometry (GC–MS) method was developed and validated for the simultaneous qualification and quantification of methamphetamine (MA), amphetamine (AP), 3,4-methylenedioxy-N-methylamphetamine (MDMA), 3,4-methylenedioxy-N-amphetamine (MDA), ketamine (KET) and norketamine (NKT) in fingernails. Fingernail samples (20 mg) were washed with distilled water and methanol, digested with 1.0 M sodium hydroxide at 95 °C for 30 min, and then extracted with ethyl acetate. Extract solutions were evaporated to dryness, derivatized using heptafluorobutyric anhydride (HFBA) at 60 °C for 30 min, and analyzed by GC–MS. The linear ranges were 0.1–20.0 ng/mg for AP, MDMA and NKT, 0.2–20.0 ng/mg for MA and MDA, and 0.4–20.0 ng/mg for KET, with the coefficients of determination (r2  0.9989). The intra- and inter-day precisions were within 7.1% and 10.6%, respectively. The intra- and inter-day accuracies were ?10.9% to 0.8% and ?4.3% to 4.5%, respectively. The limits of detections (LODs) and the limits of quantifications (LOQs) for each analyte were lower than 0.094 ng/mg and 0.314 ng/mg, respectively. The recoveries were in the range of 72.3–94.9%. The average fingernail growth rates of two subjects for three years and six subjects for two months were 3.12 mm/month and 3.16 mm/month, respectively. The method proved to be suitable also for the simultaneous detection and quantification of MA, MDMA, KET and their metabolites in fingernails.  相似文献   
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178.
The Widmark formula has been widely adopted in forensic applications to drink driving cases for the last 70 years. It is known that the amount of alcohol consumed and the body weight of the drinkers are important information for the estimation of blood alcohol concentration (BAC). However, the direct application of the Widmark factors derived from Caucasian to the calculation of BAC for the Chinese population often encounters serious challenges. Owing to this inherent weakness, a thorough analysis to determine the theoretical Widmark factors for the Chinese population, r(0) at the start of drinking and the practical factors, r(peak), at peak BAC was conducted. In the present study, other factors such as gender, stomach condition and other physiological conditions are taken into account. The determined theoretical Widmark factors, r(0,) for local Chinese male and female are 0.68 and 0.59 (with BAC in the units of weight/volume), respectively, demonstrating the applicability of the Widmark formula to the Chinese population. The practical factors at peak BAC, r(peak), were also determined to serve the forensic purpose of refuting the "hip-flask" defence in drink driving cases. Findings show that gender and stomach condition are the key factors that could statistically explain the variability of both r(0) and r(peak).  相似文献   
179.
180.
After Hong Kong is integrated with mainland China in July 1997, the economic and political environments of the two places will inevitably link up with each other. Economic modernization significantly not only improves the living conditions of the Chinese, but also alters their social structure and political values. As such, economic prosperity and democracy become the two conflicting values in Hong Kong and China during the transition to 2000. The people of Hong Kong and China are presented a choice over two mutually exclusive targets: economic prosperity vs. democracy. On the one hand, the choice for economic prosperity will imply no democracy because a conservative political system will be maintained to preserve the political status quo. On the other hand, the choice for democracy will imply no economic prosperity, because democratization will be suppressed and hence the economy will suffer as a result of political instability. However, neither of these two choices could offer the people of Hong Kong and China a genuine prosperity and stability. Therefore a congruent relationship between the economy and the political system must be established and maintained. As prosperity is contributed by both economic growth and political stability, neglection of either of these two elements will not result in a long‐lasting prosperity. Thus, economic development and democratization are two complementary rather than contradicting forces on the road to development in China.  相似文献   
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